I would argue that genes play a larger role than given credit. For example, Pacific Islanders evolved to survive on a minimal diet of plants and fish — not a lot of red meat available on small islands. After millions of years evolving their systems to handle mostly fish as their source of meat, they now have easy access to red and white meat in the form of McDonalds and KFC. Their bodies don’t metabolize these meats as well as they do fish, so what you end up with is the stereotypical ‘big fat Samoan.’ I doubt islanders are very well educated on their ancestral diets, so it’s not as simple as saying “eat less red meat” for them. In reality, they should cut all red meat and go back to eating fish. Easier said than done. Point being, different body types and ancestral genes determine which diet is best for an individual. A diet that works best for a Samoan probably won’t work well for an Anglo North American, and vice versa.
